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        <h2>
          <span class="refentrytitle">expsega</span>
        </h2>
        <p>expsega — 
      An exponential segment generator operating at a-rate.
          </p>
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      <div class="refsect1">
        <a id="idp101957744"></a>
        <h2>Description</h2>
        <p>
      An exponential segment generator operating at a-rate. This unit is almost identical to <a class="link" href="expseg.html" title="expseg"><em class="citetitle">expseg</em></a>, but more precise when defining segments with very short durations (i.e., in a percussive attack phase) at audio rate.
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      <div class="refsect1">
        <a id="idp101960128"></a>
        <h2>Syntax</h2>
        <pre class="synopsis">ares <span class="command"><strong>expsega</strong></span> ia, idur1, ib [, idur2] [, ic] [...]</pre>
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      <div class="refsect1">
        <a id="idp101962384"></a>
        <h2>Initialization</h2>
        <p>
      <span class="emphasis"><em>ia</em></span> -- starting value. Zero is illegal.
    </p>
        <p>
      <span class="emphasis"><em>ib</em></span>, <span class="emphasis"><em>ic</em></span>, etc. -- value after <span class="emphasis"><em>idur1</em></span> seconds, etc. must be non-zero and must agree in sign with <span class="emphasis"><em>ia</em></span>.
    </p>
        <p>
      <span class="emphasis"><em>idur1</em></span> -- duration in seconds of first segment. A zero or negative value will cause all initialization to be skipped.
    </p>
        <p>
      <span class="emphasis"><em>idur2</em></span>, <span class="emphasis"><em>idur3</em></span>, etc. -- duration in seconds of subsequent segments. A zero or negative value will terminate the initialization process with the preceding point, permitting the last defined line or curve to be continued indefinitely in performance. The default is zero.
    </p>
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      <div class="refsect1">
        <a id="idp101969040"></a>
        <h2>Performance</h2>
        <p>
      This unit generate audio signals whose values can pass through two or more specified points. The sum of <span class="emphasis"><em>dur</em></span> values may or may not equal the instrument's performance time. A shorter performance will truncate the specified pattern, while a longer one will cause the last defined segment to continue on in the same direction.
    </p>
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      <div class="refsect1">
        <a id="idp101971232"></a>
        <h2>Examples</h2>
        <p>
      Here is an example of the expsega opcode. It uses the file <a class="ulink" href="examples/expsega.csd" target="_top"><em class="citetitle">expsega.csd</em></a>.

      </p>
        <div class="example">
          <a id="idp101973088"></a>
          <p class="title">
            <strong>Example 239. Example of the expsega opcode.</strong>
          </p>
          <div class="example-contents">
            <p>See the sections <a class="link" href="UsingRealTime.html" title="Real-Time Audio"><em class="citetitle">Real-time Audio</em></a> and <a class="link" href="CommandFlags.html" title="Csound command line"><em class="citetitle">Command Line Flags</em></a> for more information on using command line flags.</p>
            <pre class="programlisting">
<span class="csdtag">&lt;CsoundSynthesizer&gt;</span>
<span class="csdtag">&lt;CsOptions&gt;</span>
<span class="comment">; Select audio/midi flags here according to platform</span>
<span class="comment">; Audio out   Audio in    No messages</span>
-odac           -iadc     -d     <span class="comment">;;;RT audio I/O</span>
<span class="comment">; For Non-realtime ouput leave only the line below:</span>
<span class="comment">; -o expsega.wav -W ;;; for file output any platform</span>
<span class="csdtag">&lt;/CsOptions&gt;</span>
<span class="csdtag">&lt;CsInstruments&gt;</span>

<span class="comment">; Initialize the global variables.</span>
<span class="ohdr">sr</span> <span class="op">=</span> 44100
<span class="ohdr">kr</span> <span class="op">=</span> 4410
<span class="ohdr">ksmps</span> <span class="op">=</span> 10
<span class="ohdr">nchnls</span> <span class="op">=</span> 1

<span class="comment">; Instrument #1.</span>
<span class="oblock">instr</span> 1
  <span class="comment">; Define a short percussive amplitude envelope that</span>
  <span class="comment">; goes from 0.01 to 20,000 and back.</span>
  aenv <span class="opc">expsega</span> 0.01, 0.1, 20000, 0.1, 0.01

  a1 <span class="opc">oscil</span> aenv, 440, 1
  <span class="opc">out</span> a1
<span class="oblock">endin</span>


<span class="csdtag">&lt;/CsInstruments&gt;</span>
<span class="csdtag">&lt;CsScore&gt;</span>

<span class="comment">; Table #1, a sine wave.</span>
<span class="stamnt">f</span> 1 0 16384 10 1

<span class="comment">; Play Instrument #1 for one second.</span>
<span class="stamnt">i</span> 1 0 1
<span class="comment">; Play Instrument #1 for one second.</span>
<span class="stamnt">i</span> 1 1 1
<span class="comment">; Play Instrument #1 for one second.</span>
<span class="stamnt">i</span> 1 2 1
<span class="comment">; Play Instrument #1 for one second.</span>
<span class="stamnt">i</span> 1 3 1
<span class="stamnt">e</span>


<span class="csdtag">&lt;/CsScore&gt;</span>
<span class="csdtag">&lt;/CsoundSynthesizer&gt;</span>
</pre>
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        <p><br class="example-break" />
    </p>
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      <div class="refsect1">
        <a id="idp101977408"></a>
        <h2>See Also</h2>
        <p>
      <a class="link" href="expseg.html" title="expseg"><em class="citetitle">expseg</em></a>, 
      <a class="link" href="expsegr.html" title="expsegr"><em class="citetitle">expsegr</em></a>
    </p>
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      <div class="refsect1">
        <a id="idp101980480"></a>
        <h2>Credits</h2>
        <p>Author: Gabriel Maldonado</p>
        <p>Example written by Kevin Conder.</p>
        <p>New in Csound 3.57</p>
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